Biphasic compositions comprising one or both of carbonate and phosphate
Various aspects of this disclosure relate to biphasic compositions comprising one or both of solid-phase carbonate and solid-phase phosphate, which are capable of buffering a liquid phase to stabilize a liquid-phase anion.
1. A composition, comprising each of a buffer, a conjugate acid, an excipient, an anion, and a solvent at both a concentration by mass and an amount by mole, wherein:
the anion is selected from the group consisting of 3-hydroxy-2-geranyl-5-pentylphenolate, and 3-hydroxy-5-pentyl-2-(3-methyl-6-isopropenylcyclohex-2-enyl) phenolate, and combinations thereof
the composition comprises the buffer and the conjugate acid at a combined concentration by mass of at least 0.05 percent and no greater than 2 percent;
the concentration by mass of the excipient in the composition is greater than the combined concentration by mass of the buffer and the conjugate acid in the composition;
the concentration by mass of the solvent in the composition is greater than the concentration by mass of the anion in the composition; the composition comprises the buffer and the conjugate acid at a combined amount by mole that is greater than the amount by mole of the anion in the composition;
the amount by mole of the solvent in the composition is at least 5 times greater than the amount by mole of the anion in the composition; the composition comprises the buffer and the conjugate acid at a ratio by mole of at least 1:800 and no greater than 80:1;
the composition comprises a solid phase at a concentration of at least 88 percent and no greater than 98 percent by mass;
the composition comprises a liquid phase at a concentration of at least 2 percent and no greater than 12 percent by mass;
the solid phase and the liquid phase are in chemical communication such that buffer, conjugate acid, and excipient of the solid phase can dissolve into the liquid phase and such that buffer, conjugate acid, and excipient of the liquid phase can precipitate into the solid phase;
the buffer has a solubility in the liquid phase, which is the maximum mass of the buffer that will dissolve in the liquid phase at thermodynamic equilibrium per volume of the liquid phase;
the conjugate acid has a solubility in the liquid phase, which is the maximum mass of the conjugate acid that will dissolve in the liquid phase at thermodynamic equilibrium per volume of the liquid phase;
the composition comprises one or both of (i) a mass-to-volume ratio of buffer-to-liquid-phase that is greater than the solubility of the buffer in the liquid phase and (ii) a mass-to-volume ratio of conjugate acid-to-liquid-phase that is greater than the solubility of the conjugate acid in the liquid phase;
the excipient has a solubility in the liquid phase, which is the maximum mass of the excipient that will dissolve in the liquid phase at thermodynamic equilibrium per volume of the liquid phase;
the composition comprises a mass-to-volume ratio of excipient-to-liquid-phase that is greater than the solubility of the excipient in the liquid phase;
each of the buffer, the conjugate acid, and the anion have an association constant for protonation in water at 20 degrees Celsius (“Kb,buffer”, “Kb, conjugate acid”, and “Kb,anion”);
the association constant for protonation of the anion is both greater than 10 times the association constant for protonation of the conjugate acid and less than the product of the association constant for protonation of the buffer and the ratio by mole of the buffer and the conjugate acid (10×Kb, conjugate acid<Kb,anion<Kb,buffer×ratio by mole of the buffer and the conjugate acid);
the liquid phase comprises each of the anion and the solvent at both an amount by mass and an amount by mole;
the amount by mass of the solvent in the liquid phase is greater than the amount by mass of the anion in the liquid phase;
the amount by mole of the solvent in the liquid phase is at least 5 times greater than the amount by mole of the anion in the liquid phase; the liquid phase lacks each of the buffer, the conjugate acid, and the excipient at an amount by mole that is greater than the amount by mole of the solvent in the liquid phase;
the solid phase lacks an amount by mass of the anion that is greater than the amount by mass of the anion in the liquid phase;
the solid phase lacks an amount by mass of the solvent that is greater than the amount by mass of the solvent in the liquid phase; the solid phase comprises the excipient at an amount by mass;
the solid phase comprises the buffer and the conjugate acid at a combined amount by mass that is less than the amount by mass of the excipient in the solid phase; and
the liquid phase lacks an amount by mass of the excipient that is greater than the amount by mass of the excipient in the solid phase.
2. The composition of claim 1 , wherein the buffer is carbonate.
3. The composition of claim 1 , wherein the buffer is a carbonate salt.
4. The composition of claim 1 , wherein the buffer is sodium carbonate or potassium carbonate.
5. The composition of claim 1 , wherein the buffer is phosphate.
6. The composition of claim 1 , wherein the buffer is a phosphate salt.
7. The composition of claim 1 , wherein the buffer is trisodium phosphate or tripotassium phosphate.
8. The composition of claim 1 , comprising the buffer and the conjugate acid at a combined concentration by mass of no greater than 0.2 percent.
9. The composition of claim 1 , comprising the buffer and the conjugate acid at a combined concentration by mass of no greater than 0.1 percent.